| /* SPDX-License-Identifier: LGPL-2.1-or-later */ |
| |
| #include "in-addr-util.h" |
| #include "resolved-dns-synthesize.h" |
| #include "resolved-varlink.h" |
| #include "socket-netlink.h" |
| |
| typedef struct LookupParameters { |
| int ifindex; |
| uint64_t flags; |
| int family; |
| union in_addr_union address; |
| size_t address_size; |
| char *name; |
| } LookupParameters; |
| |
| static void lookup_parameters_destroy(LookupParameters *p) { |
| assert(p); |
| free(p->name); |
| } |
| |
| static int reply_query_state(DnsQuery *q) { |
| |
| assert(q); |
| assert(q->varlink_request); |
| |
| switch (q->state) { |
| |
| case DNS_TRANSACTION_NO_SERVERS: |
| return varlink_error(q->varlink_request, "io.systemd.Resolve.NoNameServers", NULL); |
| |
| case DNS_TRANSACTION_TIMEOUT: |
| return varlink_error(q->varlink_request, "io.systemd.Resolve.QueryTimedOut", NULL); |
| |
| case DNS_TRANSACTION_ATTEMPTS_MAX_REACHED: |
| return varlink_error(q->varlink_request, "io.systemd.Resolve.MaxAttemptsReached", NULL); |
| |
| case DNS_TRANSACTION_INVALID_REPLY: |
| return varlink_error(q->varlink_request, "io.systemd.Resolve.InvalidReply", NULL); |
| |
| case DNS_TRANSACTION_ERRNO: |
| return varlink_error_errno(q->varlink_request, q->answer_errno); |
| |
| case DNS_TRANSACTION_ABORTED: |
| return varlink_error(q->varlink_request, "io.systemd.Resolve.QueryAborted", NULL); |
| |
| case DNS_TRANSACTION_DNSSEC_FAILED: |
| return varlink_errorb(q->varlink_request, "io.systemd.Resolve.DNSSECValidationFailed", |
| JSON_BUILD_OBJECT(JSON_BUILD_PAIR("result", JSON_BUILD_STRING(dnssec_result_to_string(q->answer_dnssec_result))))); |
| |
| case DNS_TRANSACTION_NO_TRUST_ANCHOR: |
| return varlink_error(q->varlink_request, "io.systemd.Resolve.NoTrustAnchor", NULL); |
| |
| case DNS_TRANSACTION_RR_TYPE_UNSUPPORTED: |
| return varlink_error(q->varlink_request, "io.systemd.Resolve.ResourceRecordTypeUnsupported", NULL); |
| |
| case DNS_TRANSACTION_NETWORK_DOWN: |
| return varlink_error(q->varlink_request, "io.systemd.Resolve.NetworkDown", NULL); |
| |
| case DNS_TRANSACTION_NOT_FOUND: |
| /* We return this as NXDOMAIN. This is only generated when a host doesn't implement LLMNR/TCP, and we |
| * thus quickly know that we cannot resolve an in-addr.arpa or ip6.arpa address. */ |
| return varlink_errorb(q->varlink_request, "io.systemd.Resolve.DNSError", |
| JSON_BUILD_OBJECT(JSON_BUILD_PAIR("rcode", JSON_BUILD_INTEGER(DNS_RCODE_NXDOMAIN)))); |
| |
| case DNS_TRANSACTION_RCODE_FAILURE: |
| return varlink_errorb(q->varlink_request, "io.systemd.Resolve.DNSError", |
| JSON_BUILD_OBJECT(JSON_BUILD_PAIR("rcode", JSON_BUILD_INTEGER(q->answer_rcode)))); |
| |
| case DNS_TRANSACTION_NULL: |
| case DNS_TRANSACTION_PENDING: |
| case DNS_TRANSACTION_VALIDATING: |
| case DNS_TRANSACTION_SUCCESS: |
| default: |
| assert_not_reached("Impossible state"); |
| } |
| } |
| |
| static void vl_on_disconnect(VarlinkServer *s, Varlink *link, void *userdata) { |
| DnsQuery *q; |
| |
| assert(s); |
| assert(link); |
| |
| q = varlink_get_userdata(link); |
| if (!q) |
| return; |
| |
| if (!DNS_TRANSACTION_IS_LIVE(q->state)) |
| return; |
| |
| log_debug("Client of active query vanished, aborting query."); |
| dns_query_complete(q, DNS_TRANSACTION_ABORTED); |
| } |
| |
| static bool validate_and_mangle_flags( |
| const char *name, |
| uint64_t *flags, |
| uint64_t ok) { |
| |
| assert(flags); |
| |
| /* This checks that the specified client-provided flags parameter actually makes sense, and mangles |
| * it slightly. Specifically: |
| * |
| * 1. We check that only the protocol flags and the NO_CNAME flag are on at most, plus the |
| * method-specific flags specified in 'ok'. |
| * |
| * 2. If no protocols are enabled we automatically convert that to "all protocols are enabled". |
| * |
| * The second rule means that clients can just pass 0 as flags for the common case, and all supported |
| * protocols are enabled. Moreover it's useful so that client's do not have to be aware of all |
| * protocols implemented in resolved, but can use 0 as protocols flags set as indicator for |
| * "everything". |
| */ |
| |
| if (*flags & ~(SD_RESOLVED_PROTOCOLS_ALL|SD_RESOLVED_NO_CNAME|ok)) |
| return false; |
| |
| if ((*flags & SD_RESOLVED_PROTOCOLS_ALL) == 0) /* If no protocol is enabled, enable all */ |
| *flags |= SD_RESOLVED_PROTOCOLS_ALL; |
| |
| /* If the SD_RESOLVED_NO_SEARCH flag is acceptable, and the query name is dot-suffixed, turn off |
| * search domains. Note that DNS name normalization drops the dot suffix, hence we propagate this |
| * into the flags field as early as we can. */ |
| if (name && FLAGS_SET(ok, SD_RESOLVED_NO_SEARCH) && dns_name_dot_suffixed(name) > 0) |
| *flags |= SD_RESOLVED_NO_SEARCH; |
| |
| return true; |
| } |
| |
| static void vl_method_resolve_hostname_complete(DnsQuery *q) { |
| _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *canonical = NULL; |
| _cleanup_(json_variant_unrefp) JsonVariant *array = NULL; |
| _cleanup_free_ char *normalized = NULL; |
| DnsResourceRecord *rr; |
| DnsQuestion *question; |
| int ifindex, r; |
| |
| assert(q); |
| |
| if (q->state != DNS_TRANSACTION_SUCCESS) { |
| r = reply_query_state(q); |
| goto finish; |
| } |
| |
| r = dns_query_process_cname(q); |
| if (r == -ELOOP) { |
| r = varlink_error(q->varlink_request, "io.systemd.Resolve.CNAMELoop", NULL); |
| goto finish; |
| } |
| if (r < 0) |
| goto finish; |
| if (r == DNS_QUERY_RESTARTED) /* This was a cname, and the query was restarted. */ |
| return; |
| |
| question = dns_query_question_for_protocol(q, q->answer_protocol); |
| |
| DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, q->answer) { |
| _cleanup_(json_variant_unrefp) JsonVariant *entry = NULL; |
| int family; |
| const void *p; |
| |
| r = dns_question_matches_rr(question, rr, DNS_SEARCH_DOMAIN_NAME(q->answer_search_domain)); |
| if (r < 0) |
| goto finish; |
| if (r == 0) |
| continue; |
| |
| if (rr->key->type == DNS_TYPE_A) { |
| family = AF_INET; |
| p = &rr->a.in_addr; |
| } else if (rr->key->type == DNS_TYPE_AAAA) { |
| family = AF_INET6; |
| p = &rr->aaaa.in6_addr; |
| } else { |
| r = -EAFNOSUPPORT; |
| goto finish; |
| } |
| |
| r = json_build(&entry, |
| JSON_BUILD_OBJECT( |
| JSON_BUILD_PAIR("ifindex", JSON_BUILD_INTEGER(ifindex)), |
| JSON_BUILD_PAIR("family", JSON_BUILD_INTEGER(family)), |
| JSON_BUILD_PAIR("address", JSON_BUILD_BYTE_ARRAY(p, FAMILY_ADDRESS_SIZE(family))))); |
| if (r < 0) |
| goto finish; |
| |
| if (!canonical) |
| canonical = dns_resource_record_ref(rr); |
| |
| r = json_variant_append_array(&array, entry); |
| if (r < 0) |
| goto finish; |
| } |
| |
| if (json_variant_is_blank_object(array)) { |
| r = varlink_error(q->varlink_request, "io.systemd.Resolve.NoSuchResourceRecord", NULL); |
| goto finish; |
| } |
| |
| assert(canonical); |
| r = dns_name_normalize(dns_resource_key_name(canonical->key), 0, &normalized); |
| if (r < 0) |
| goto finish; |
| |
| r = varlink_replyb(q->varlink_request, |
| JSON_BUILD_OBJECT( |
| JSON_BUILD_PAIR("addresses", JSON_BUILD_VARIANT(array)), |
| JSON_BUILD_PAIR("name", JSON_BUILD_STRING(normalized)), |
| JSON_BUILD_PAIR("flags", JSON_BUILD_INTEGER(SD_RESOLVED_FLAGS_MAKE(q->answer_protocol, q->answer_family, dns_query_fully_authenticated(q)))))); |
| finish: |
| if (r < 0) { |
| log_error_errno(r, "Failed to send hostname reply: %m"); |
| r = varlink_error_errno(q->varlink_request, r); |
| } |
| |
| dns_query_free(q); |
| } |
| |
| static int parse_as_address(Varlink *link, LookupParameters *p) { |
| _cleanup_free_ char *canonical = NULL; |
| int r, ff, parsed_ifindex, ifindex; |
| union in_addr_union parsed; |
| |
| assert(link); |
| assert(p); |
| |
| /* Check if this parses as literal address. If so, just parse it and return that, do not involve networking */ |
| r = in_addr_ifindex_from_string_auto(p->name, &ff, &parsed, &parsed_ifindex); |
| if (r < 0) |
| return 0; /* not a literal address */ |
| |
| /* Make sure the data we parsed matches what is requested */ |
| if ((p->family != AF_UNSPEC && ff != p->family) || |
| (p->ifindex > 0 && parsed_ifindex > 0 && parsed_ifindex != p->ifindex)) |
| return varlink_error(link, "io.systemd.Resolve.NoSuchResourceRecord", NULL); |
| |
| ifindex = parsed_ifindex > 0 ? parsed_ifindex : p->ifindex; |
| |
| /* Reformat the address as string, to return as canonicalized name */ |
| r = in_addr_ifindex_to_string(ff, &parsed, ifindex, &canonical); |
| if (r < 0) |
| return r; |
| |
| return varlink_replyb( |
| link, |
| JSON_BUILD_OBJECT( |
| JSON_BUILD_PAIR("addresses", |
| JSON_BUILD_ARRAY( |
| JSON_BUILD_OBJECT( |
| JSON_BUILD_PAIR_CONDITION(ifindex > 0, "ifindex", JSON_BUILD_INTEGER(ifindex)), |
| JSON_BUILD_PAIR("family", JSON_BUILD_INTEGER(ff)), |
| JSON_BUILD_PAIR("address", JSON_BUILD_BYTE_ARRAY(&parsed, FAMILY_ADDRESS_SIZE(ff)))))), |
| JSON_BUILD_PAIR("name", JSON_BUILD_STRING(canonical)), |
| JSON_BUILD_PAIR("flags", JSON_BUILD_INTEGER(SD_RESOLVED_FLAGS_MAKE(dns_synthesize_protocol(p->flags), ff, true))))); |
| } |
| |
| static int vl_method_resolve_hostname(Varlink *link, JsonVariant *parameters, VarlinkMethodFlags flags, void *userdata) { |
| static const JsonDispatch dispatch_table[] = { |
| { "ifindex", JSON_VARIANT_UNSIGNED, json_dispatch_int, offsetof(LookupParameters, ifindex), 0 }, |
| { "name", JSON_VARIANT_STRING, json_dispatch_string, offsetof(LookupParameters, name), JSON_MANDATORY }, |
| { "family", JSON_VARIANT_UNSIGNED, json_dispatch_int, offsetof(LookupParameters, family), 0 }, |
| { "flags", JSON_VARIANT_UNSIGNED, json_dispatch_uint64, offsetof(LookupParameters, flags), 0 }, |
| {} |
| }; |
| |
| _cleanup_(dns_question_unrefp) DnsQuestion *question_idna = NULL, *question_utf8 = NULL; |
| _cleanup_(lookup_parameters_destroy) LookupParameters p = { |
| .family = AF_UNSPEC, |
| }; |
| Manager *m = userdata; |
| DnsQuery *q; |
| int r; |
| |
| assert(link); |
| assert(m); |
| |
| if (FLAGS_SET(flags, VARLINK_METHOD_ONEWAY)) |
| return -EINVAL; |
| |
| r = json_dispatch(parameters, dispatch_table, NULL, 0, &p); |
| if (r < 0) |
| return r; |
| |
| if (p.ifindex < 0) |
| return varlink_error_invalid_parameter(link, JSON_VARIANT_STRING_CONST("ifindex")); |
| |
| r = dns_name_is_valid(p.name); |
| if (r < 0) |
| return r; |
| if (r == 0) |
| return varlink_error_invalid_parameter(link, JSON_VARIANT_STRING_CONST("name")); |
| |
| if (!IN_SET(p.family, AF_UNSPEC, AF_INET, AF_INET6)) |
| return varlink_error_invalid_parameter(link, JSON_VARIANT_STRING_CONST("family")); |
| |
| if (!validate_and_mangle_flags(p.name, &p.flags, SD_RESOLVED_NO_SEARCH)) |
| return varlink_error_invalid_parameter(link, JSON_VARIANT_STRING_CONST("flags")); |
| |
| r = parse_as_address(link, &p); |
| if (r != 0) |
| return r; |
| |
| r = dns_question_new_address(&question_utf8, p.family, p.name, false); |
| if (r < 0) |
| return r; |
| |
| r = dns_question_new_address(&question_idna, p.family, p.name, true); |
| if (r < 0 && r != -EALREADY) |
| return r; |
| |
| r = dns_query_new(m, &q, question_utf8, question_idna ?: question_utf8, p.ifindex, p.flags); |
| if (r < 0) |
| return r; |
| |
| q->varlink_request = varlink_ref(link); |
| varlink_set_userdata(link, q); |
| q->request_family = p.family; |
| q->complete = vl_method_resolve_hostname_complete; |
| |
| r = dns_query_go(q); |
| if (r < 0) |
| goto fail; |
| |
| return 1; |
| |
| fail: |
| dns_query_free(q); |
| return r; |
| } |
| |
| static int json_dispatch_address(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata) { |
| LookupParameters *p = userdata; |
| union in_addr_union buf = {}; |
| JsonVariant *i; |
| size_t n, k = 0; |
| |
| assert(variant); |
| assert(p); |
| |
| if (!json_variant_is_array(variant)) |
| return json_log(variant, flags, SYNTHETIC_ERRNO(EINVAL), "JSON field '%s' is not an array.", strna(name)); |
| |
| n = json_variant_elements(variant); |
| if (!IN_SET(n, 4, 16)) |
| return json_log(variant, flags, SYNTHETIC_ERRNO(EINVAL), "JSON field '%s' is array of unexpected size.", strna(name)); |
| |
| JSON_VARIANT_ARRAY_FOREACH(i, variant) { |
| intmax_t b; |
| |
| if (!json_variant_is_integer(i)) |
| return json_log(variant, flags, SYNTHETIC_ERRNO(EINVAL), "Element %zu of JSON field '%s' is not an integer.", k, strna(name)); |
| |
| b = json_variant_integer(i); |
| if (b < 0 || b > 0xff) |
| return json_log(variant, flags, SYNTHETIC_ERRNO(EINVAL), "Element %zu of JSON field '%s' is out of range 0…255.", k, strna(name)); |
| |
| buf.bytes[k++] = (uint8_t) b; |
| } |
| |
| p->address = buf; |
| p->address_size = k; |
| |
| return 0; |
| } |
| |
| static void vl_method_resolve_address_complete(DnsQuery *q) { |
| _cleanup_(json_variant_unrefp) JsonVariant *array = NULL; |
| DnsQuestion *question; |
| DnsResourceRecord *rr; |
| int ifindex, r; |
| |
| assert(q); |
| |
| if (q->state != DNS_TRANSACTION_SUCCESS) { |
| r = reply_query_state(q); |
| goto finish; |
| } |
| |
| r = dns_query_process_cname(q); |
| if (r == -ELOOP) { |
| r = varlink_error(q->varlink_request, "io.systemd.Resolve.CNAMELoop", NULL); |
| goto finish; |
| } |
| if (r < 0) |
| goto finish; |
| if (r == DNS_QUERY_RESTARTED) /* This was a cname, and the query was restarted. */ |
| return; |
| |
| question = dns_query_question_for_protocol(q, q->answer_protocol); |
| |
| DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, q->answer) { |
| _cleanup_(json_variant_unrefp) JsonVariant *entry = NULL; |
| _cleanup_free_ char *normalized = NULL; |
| |
| r = dns_question_matches_rr(question, rr, NULL); |
| if (r < 0) |
| goto finish; |
| if (r == 0) |
| continue; |
| |
| r = dns_name_normalize(rr->ptr.name, 0, &normalized); |
| if (r < 0) |
| goto finish; |
| |
| r = json_build(&entry, |
| JSON_BUILD_OBJECT( |
| JSON_BUILD_PAIR("ifindex", JSON_BUILD_INTEGER(ifindex)), |
| JSON_BUILD_PAIR("name", JSON_BUILD_STRING(normalized)))); |
| if (r < 0) |
| goto finish; |
| |
| r = json_variant_append_array(&array, entry); |
| if (r < 0) |
| goto finish; |
| } |
| |
| if (json_variant_is_blank_object(array)) { |
| r = varlink_error(q->varlink_request, "io.systemd.Resolve.NoSuchResourceRecord", NULL); |
| goto finish; |
| } |
| |
| r = varlink_replyb(q->varlink_request, |
| JSON_BUILD_OBJECT( |
| JSON_BUILD_PAIR("names", JSON_BUILD_VARIANT(array)), |
| JSON_BUILD_PAIR("flags", JSON_BUILD_INTEGER(SD_RESOLVED_FLAGS_MAKE(q->answer_protocol, q->answer_family, dns_query_fully_authenticated(q)))))); |
| finish: |
| if (r < 0) { |
| log_error_errno(r, "Failed to send address reply: %m"); |
| r = varlink_error_errno(q->varlink_request, r); |
| } |
| |
| dns_query_free(q); |
| } |
| |
| static int vl_method_resolve_address(Varlink *link, JsonVariant *parameters, VarlinkMethodFlags flags, void *userdata) { |
| static const JsonDispatch dispatch_table[] = { |
| { "ifindex", JSON_VARIANT_UNSIGNED, json_dispatch_int, offsetof(LookupParameters, ifindex), 0 }, |
| { "family", JSON_VARIANT_UNSIGNED, json_dispatch_int, offsetof(LookupParameters, family), JSON_MANDATORY }, |
| { "address", JSON_VARIANT_ARRAY, json_dispatch_address, 0, JSON_MANDATORY }, |
| { "flags", JSON_VARIANT_UNSIGNED, json_dispatch_uint64, offsetof(LookupParameters, flags), 0 }, |
| {} |
| }; |
| |
| _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL; |
| _cleanup_(lookup_parameters_destroy) LookupParameters p = { |
| .family = AF_UNSPEC, |
| }; |
| Manager *m = userdata; |
| DnsQuery *q; |
| int r; |
| |
| assert(link); |
| assert(m); |
| |
| if (FLAGS_SET(flags, VARLINK_METHOD_ONEWAY)) |
| return -EINVAL; |
| |
| r = json_dispatch(parameters, dispatch_table, NULL, 0, &p); |
| if (r < 0) |
| return r; |
| |
| if (p.ifindex < 0) |
| return varlink_error_invalid_parameter(link, JSON_VARIANT_STRING_CONST("ifindex")); |
| |
| if (!IN_SET(p.family, AF_UNSPEC, AF_INET, AF_INET6)) |
| return varlink_error_invalid_parameter(link, JSON_VARIANT_STRING_CONST("family")); |
| |
| if (FAMILY_ADDRESS_SIZE(p.family) != p.address_size) |
| return varlink_error(link, "io.systemd.UserDatabase.BadAddressSize", NULL); |
| |
| if (!validate_and_mangle_flags(NULL, &p.flags, 0)) |
| return varlink_error_invalid_parameter(link, JSON_VARIANT_STRING_CONST("flags")); |
| |
| r = dns_question_new_reverse(&question, p.family, &p.address); |
| if (r < 0) |
| return r; |
| |
| r = dns_query_new(m, &q, question, question, p.ifindex, p.flags|SD_RESOLVED_NO_SEARCH); |
| if (r < 0) |
| return r; |
| |
| q->varlink_request = varlink_ref(link); |
| varlink_set_userdata(link, q); |
| |
| q->request_family = p.family; |
| q->request_address = p.address; |
| q->complete = vl_method_resolve_address_complete; |
| |
| r = dns_query_go(q); |
| if (r < 0) |
| goto fail; |
| |
| return 1; |
| |
| fail: |
| dns_query_free(q); |
| return r; |
| } |
| |
| int manager_varlink_init(Manager *m) { |
| _cleanup_(varlink_server_unrefp) VarlinkServer *s = NULL; |
| int r; |
| |
| assert(m); |
| |
| if (m->varlink_server) |
| return 0; |
| |
| r = varlink_server_new(&s, VARLINK_SERVER_ACCOUNT_UID); |
| if (r < 0) |
| return log_error_errno(r, "Failed to allocate varlink server object: %m"); |
| |
| varlink_server_set_userdata(s, m); |
| |
| r = varlink_server_bind_method_many( |
| s, |
| "io.systemd.Resolve.ResolveHostname", vl_method_resolve_hostname, |
| "io.systemd.Resolve.ResolveAddress", vl_method_resolve_address); |
| if (r < 0) |
| return log_error_errno(r, "Failed to register varlink methods: %m"); |
| |
| r = varlink_server_bind_disconnect(s, vl_on_disconnect); |
| if (r < 0) |
| return log_error_errno(r, "Failed to register varlink disconnect handler: %m"); |
| |
| r = varlink_server_listen_address(s, "/run/systemd/resolve/io.systemd.Resolve", 0666); |
| if (r < 0) |
| return log_error_errno(r, "Failed to bind to varlink socket: %m"); |
| |
| r = varlink_server_attach_event(s, m->event, SD_EVENT_PRIORITY_NORMAL); |
| if (r < 0) |
| return log_error_errno(r, "Failed to attach varlink connection to event loop: %m"); |
| |
| m->varlink_server = TAKE_PTR(s); |
| return 0; |
| } |
| |
| void manager_varlink_done(Manager *m) { |
| assert(m); |
| |
| m->varlink_server = varlink_server_unref(m->varlink_server); |
| } |